Optical waveguide switches in silicon based on Ge-indiffused waveguides

An optical waveguide switch based on single-moded Ge-indiffused waveguides with a lateral pin-diode structure for carrier injection has been realized. The switch is polarization independent and shows an on-off-ratio better than 16.5 dB at a wavelength of 1.3 μm. By time domain measurements the coexistence of the plasma dispersion and the thermo-optical effect is shown. Both effects are separated and quantified.